Overall Abstract The CNPRC has maintained a pedigreed colony of Indian origin rhesus macaques for over 19 years. The SPF Pedigreed Indian origin rhesus colony includes both an SPF level 1 colony negative for Simian Retrovirus (SRV), Simian Immmunodeficiency Virus (SIV) and Simian T Cell Lymphotrophic Virus (STLV) Herpes B virus (B virus) and an SPF level 2 colony free of three additional viruses including include rhesus cytomegalovirus (RhCMV), simian foamy virus (SFV), and rhesus rhadinovirus (RRV). All colony animals have MHC typing for Mamu-A*01, Mamu-A*08, and Mamu-B*01 and the colony is managed to optimize genetic diversity. No additional animal recruitment necessary. This application will expand the percentage of SPF2 rhesus while maintaining the current overall colony size. The application proposes to evaluate the possible addition of Adeno-associated virus (AAV) and Lymphocryptovirus (LCV) to a subset of SPF2 animals and the addition of Mamu B*17 to the MHC typing panel. This application will continue to collect fecal microbiome and peripheral lymphoid cells as a biorepository for use by HIV/AIDS investigators. The four principal goals of this application are: Screen the current SPF2 colony to explore the potential for the addition of AAV and LCV to the excluded agents, or more simply for adding information about these infections to our database. Develop improved and expanded screening and confirmatory tests for detection of SPF agents to facilitate maintenance of the SPF colony. This work includes new assays for agents such as tuberculosis, which represents the first SPF agent. Evaluate addition of Mamu-B*17 to the currently tracked MHC alleles, Mamu-A*01, Mamu-A*08, and Mamu- B*01. Transition the colony pedigree analysis from the current microsatellite platform to the SNP panel and validate the proposed SNP panel with existing microsatellite data. Continue the collection and storage of microbiome and lymphocyte samples in the unique biorepository of SPF2 to facilitate future research projects investigating the interaction of HIV with the host microbiome and immune system.